The silver, copper and silicon (110) surfaces in ambient environments

• Main Author: Barritt, Elizabeth
• Other Authors: Weightman, Peter; Lucas, Christopher
• Published: University of Liverpool 2013
• Subjects: 530; QC Physics
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.587433

The results presented in this thesis were part of a research programme that utilised the surface sensitive technique reflection anisotropy spectroscopy (RAS) to study the silver, copper and silicon (110) surfaces under ambient conditions. It has been shown that although the preparation of these surfaces can be less precise in ambient conditions, than when prepared in an ultra high vacuum (UHV) environment, the main features observed are similar. The features observed in the RA spectrum for the Si(110) surface in ambient conditions show good agreement with previous data performed in a UHV environment. The experiments performed using the Ag(110) surface show that when the Ag(110) crystal is heated to higher temperatures, when the oxide present will have dissociated off the surface, the ambient RA spectrum shows good agreement with experiments performed in UHV. However, the transition between surface states observed in UHV was not seen in the RA spectrum in ambient conditions. These experiments were performed using the Re(∆r/r) part of the RA spectra. However, to examine the surfaces further the Im(∆r/r) part of the RA spectra was also presented along with the azimuthal dependence of the RA spectrum. The Cu(110) surface was investigated under ambient conditions and electrochemically. It was found the surface is not stable in ambient conditions but can be stabilised electrochemically using HCl. The adsorption and desorption of Cl- was studied and the research focused on when the Cl- was desorbed from the surface leaving clean Cu(110). Under these conditions the transition between surface states at 2.10 eV in UHV was observed at a slightly higher energy of 2.20 eV in an electrochemical environment.